Geneology of Isshinryu

Isshinryu is the combination of two schools of martial arts, Master Tatsuo Shimabuku’s personal insights, and the weapons katas that Master Shimabuku found most useful for students to learn. Isshinryu was derived from Goju Ryu (Which Tatsuo learned from founder Chojun Miyagi) and Shorin Ryu (Which Tatsuo learned from founder Chotoku Kyan). Isshinryu was formed in 1954, however the name Isshinryu (Which means One Heart Method) was applied later by a student.

Goju Ryu translates as "Hard/soft way" or "Hard/soft style". Two kata from Goju Ryu are used in Isshinryu, Seiunchin and Sanchin. There are a number of similarities between these kata, which are inherited from the parent style. Both kata have tension moves in which students are taught to breathe from the stomach, in through the nose and out through the mouth. They also are very concerned with connectedness to the floor, more than any other katas in Isshinryu. Both kata are also remarkably easy to learn and most difficult to master.

Shorin Ryu (derived from Shuri-te) is named for the town in which it was developed. All other hand kata in Isshinryu are derived from Shorin Ryu (with the exception of Sunsu, developed by Tatsuo himself.) These kata are difficult to learn, because students step off attack lines, move in double rhythms, where the upper body explodes into action part way through steps and perform many steps off the typical 90 degree angle lines. Shorin Ryu is more graceful than most other hard styles of karate, which tend to be blocky looking.

Master Shimabuku's largest innovations in Isshinryu are the vertical fist punch with the thumb placed on top of the fist, the muscle/bone block, and short stances. The vertical fist is used for a number of reasons. The punch can be executed and return to chamber faster than a traditional turnover punch. It is usually more powerful, (because it is traveling on one axis without moving around) and is less susceptible to a joint lock. The placement of the thumb allows the thumb to be used as a weapon, while it is less likely to be jammed. This placement also allows a person to make a tighter fist than does the traditional placement, which is under the first two fingers. Hard blocks in Isshinryu are executed with the side of the arm; that is the part of the arm that is under the back of the hand. Most forms of karate block with the bony part of the arm. This muscle block prevents the bone from breaking as easily and also results in less bruising of the arms.

Weapons that are represented in Isshinryu are the bo, (A six foot long staff) and the sai (A trident pronged blunt short sword). Master Shimabuku also learned the tonfa (an L shaped piece of wood, like a police baton) and nunchaku (batons joined by rope) however these are not required to learn in most schools for black belt. Tirara Shinken and Yabiku Moden, who were among Okinawa’s most qualified weapons instructors at that time, taught these skills to Master Shimabuku.